Process of treating ores



Nov. 4 1924 1,513,775

W; G. WARQNG PROCESS OF TREATING ORES Filed Dec. 26, 1922 2 Sheets-Sheet 1 A drama;

New" 4 1s24. 1,513,775

W. G. \MARSNG PROCESS OF TREATING ORES Filed Dec. 26, 1922 2 Sheets-fiheet 2 i; 6 .LULJQZ T Q m M EEZ a m Eg T f- Ma No; 4,1924- y 1, 13, umrso 1 s'rnrssi rarest OFFICE.

cannon wannrc, or missom= f success or resume om.

Application "filed; December as, 1922, Serial No. 609,048.

Tocllwhomitmay concem: also avoided because ofits liability togo Be it known that I, Gnon'cn forward with the fume.- Instill otherprw, WARING, a citizen of the United, States, re- 'cesses, ores are smelted to matte and igi siding at Webb. City,--in the county of'Jasmet 1. n shaft furnaces of the usuaLty e 60 6 per. and State of Missouri, have invented with an lncidental production of more or; certain new; anduseful Improvementsin less fumejcontalning lead and zinc' (cad- Processes of Treating-v Ores, of which the mium, bismuth, .galhuin, indium, thallium, following is a specification. etc.), as well as, usually, some silver-where This invention relates to processes of that metal is present in .thepre. Rroduction 1 treating ores; and it comprises a method of of fume is usually an undesired accompanitreating complex refractor ores containing ment of the operation. Other metals, such relatively volatile and r atively 'non-volas copper, gold and silver, as well as. iron atile metals as well as non-metals, such as are collected in, the fused matte and i sulfur, arsenic, etc, such method being par-- metal which flow out from vthe hearth; or." 1 ticularly applicable, to fine ores, wherein a crucible and are t pp ff f m im to J white-hot porous mass of fuel such as coketime. In this process ore fines are not'deor coal, flux and ore-is established and mains a e since t y ho the draft, go fortained on a suitable hearth with the aid o f ward with the fame and seriously-interfere F a hot air injected in sufficient amount to mainwith the careful adjustment of "smelting. 75. tain thetemperature and a generally reducconditions. Zinc is an undesirable" element ing condition, a further supply of orefines in ores to be treated for matte or lead,s melt.. being usually blown into such mass with the ing because its va'pors iondense in the up 61, aid of high pressure air, and the, vapors cooler part of the charge, clogging the fiiel, arising from such mass are burnt or ox1diz etc. I 2:. ed byinjected secondary air at a point In the present invention, I have devised. above said mass, the resulting oxidized a method of beneficiating complex-sulfid fume being subsequently collected in the ores containing'lead'and zinc which is parusual bag filtering apparatus or otherwise sticularly applicable to fine ore, and fine ore A separated from the" accompanying gases; preparations, such as slime and flotation-" all as more fully hereinafter set forth and concentrates and to ores containing con-z" as claimed. siderable proportions of fines. In this Ores containing lead and zinc as sulfids, method I establish-and maintain in a'suita with these metals constituting the main or ble shaft chamber a porous or pervious mass" only values, are often treated by a special of ore, coke and flux, white-hot throughout; 9 process to regain these metals as sublimed The ore in this charge, or some of it, ma white lead; the ore with more or less fuel be coarse. ore., The temperature. of-the being heated with an ample supply of air charge is held at-a point sufliciently elein low shaft furnaces having an open breast fi ed. t0 yieldja fr ly flu d gh S a l g (the Scotch hearth type) or in grate furfrom the gangup minerals-present and give a Q5 40 naces. Lead and zinc compounds are thereclean separation and removal of the valuable by evolved as fume which'is caught in bags. elements. This't'e nperatui'c may be between-- The product being intended for pigmentary' 1200? and 1500 C. and is generally around. purposes must of course be pure white; and 1400 C:- according' to the compositionof. for this reason the process is not adapted slow sought. -Into' the white hot charge I-- T00 .to all ores and many precautions must be iuycrea hot blast from tuyres, using such taken to secure and preserve the purity of an amount of nir'as will maintain generally the product. Frequently a double operation reducing conditions with the formation ofis practiced; the ore being first smelted una matte containing the relatively-non-vol-' der reducing conditions to make a blue atile m t p e P} g d fume this fume being burned and the burnt pcciall'y. Much of the-silver, if present,

fume resinelted to produce a white fume or goes forward along with vapors of, zinc,

pigment. It is customary to operate at a lead, bismuth, antimony, etc. Above the temperature below that at which silicate surface of the charge I supply sectndaryair.

slags will form and liquefy; hence the ex as hot blast from tuyeres located abovethe 1m 66 traction of values is incomplete. Fine'or riorn'ialchar e ,level. Relatively volatile dustlike ore is not readily handled and is metals and sulfids as vapors are oxidized or fbamt b thi s secondary' air yielding m like oxideYfumesfz- Fineg' ore is blown into the perviousmass' through the tuyeressupplying the primary air, asupply of lngh pressure air being'used'as' injecting means. In its apparatus embodiment, the invention takes the form of a low shaft furnace located below a charging floor and provided with a hearth, slag'and matte outlets and tuyeres '10 at .a'3 loyv.1evel..- "Above thecharge level it is prbinded-rwitbtuyres for secondary air.

lheidoWer tuyeres,; xor r-some of,-them, are

rovided with. means for injecting ore fines yan'anszgofi h=pressure,air. The fine ore,;. .beingifdlanto .the glowing pervious.

" cannptfygo-jzforward. with the gases to) mass, join the fume. the; 'ore' portion ofrthe 'charg e'i ma'y -fconsistkof .fines introduced,

orthezfine .oreimayfurnish such a portion 20,ofsuchioharge asicircumstances may dietate: '(iokeforicoal and-flux are supplied to ifeplenishfihei glowing mass .bymeans of a fsu table;mechanical; intermittent feeding. device' ;throughfiaichargeopening at the top of sthes-shaita eIiEcOarse'Eore is-savailable itis supplied ivitli thejfuel; and-flux. The fuel theichargeim ixturebeing' computed to yield aslagToarrying-AO percent or-more of silica.

-'Under;the conditions of the operation the zinc 'and-leadare necessarily-volatilized and withgthemianyz cadmiumfbismuth, gallium, 'indiuin,ithallium, etc.,,that may be present.

7 The-silver, or some; of it, is also vaporized.

" Pa'ssing iup' .to the level of the secondary -tuyeresthe vapors are oxidized, or burnt, t 'pro'ducing light visible oxide fume, which is readily cahghtand retained by bag filters. The other and relatively non-volatile valuable .i'netalsof the charge form a imatte which is tapped off from the hearth continu- 5 ously' ormtermitterttly as circumstances dictate. The-gangue ombines with the flux elements to forma clean high silica slag carrying-no substantial amount of values. 1 .'.'1he fumes formed at the oxidizing tuyere' level go forward and are collected by bags or other devices, and may be treated by methods not here important to relate in detail for recovering the contained values. Being completely oxidized they are readily amenable "to treatment with waterand with the usual leaching solvents." For example, tliiume may be treated with dilute sulfuric 1; "acid or by electrolytic cell liquor to dissolve E'the'zinc, cadmium and silver; the silver and 'cadmium being subsequently removed by i -'cen'ien'tation upon metallic zinc with final deposition of the zinc by electrolysis, Or

" the'funie maybe extracted with a boiling solution of ammonium sulfate with cemen- .tation to deposit cadmium and'silver and readily wetted by aqueous liquids, such as.

by the use of the secondary airto burn the metallic vapors and carbon compounds; this cooling to separate the zinc as basic sulfate. Reference is also made to my prior patents,

Nos 1,430,269, 1,430,270 and 1,430,271..

Whenl wet methodsof extraction are. used,-

lead and bismuth and most of the silver and ,antimony remain as an insoluble residue which can be easily reduced to metallic bull'- treated in the usual ways'to recover-copper or-gold or silver, if present.

The fume made by the resent method and collected in 'bags d ers t y ,from that made by prior proc ss ion. The matte produced in the furnace .is 4

physical condition is such that it can are usedin leaching processes, rendering the stated methods of extraction easily appli- 1 cable.- This condition is probably 'duef largely to the complete oxidation afi'orded oxidation being effected immediately after the vapors leave the surface-of the incanf descent charge andbefore their temperature h l I In the accompanying illustration, I'have shown more or less dia rammatically, Qcer I has fallen below say 1 Q 1. I

tain apparatus susceptible of use in the per formance of the described-process.

In this showing, F1g..1 1s a VlBW ln.

tral vertical section, certain parts being shown in elevation along line 1-1 of F1g;2 ;"f Fig; 2 is a similar view, along section line",

2-2 of Fig. 1; and

Fig. 3 is a detail view along section-line 3-3 of Fig.1.

In this showing, element *1 'is' a low brick or masonry shaft of the general type of those known as Rachette furnaces. Above itis a charging floor 2 with rails 3-for convenient feeding of charge materials. Charge materials are introduced through an opening closed by plate 4. At its base it is.pro-' vided withremovable hearth5,; shown as carried on jacks (3, Below. the smasonry as contained within the blast pipe and concentric therewith. Beyond this injector is a sort of hopper 13 into which fine ore. may be delivered from feeding condilit 14 s'upplied'from pockets 15. As shown,thereiare two of these pockets mounted on two sides of the furnace and each provided with forwarding screws 16 adapted to feed material to pipes 17 which enter the beforementioned pipes 14:. 'By the use of these devices fine ore maybe sent forward with the blast air through the tuyeres by the use of a modicum of high pressure air. As shown the hearth slopes somewhat to a matte and slag discharge 18. Passing through the waterof about 15 inches for this charge; but a level well above the normal charge level are tuyeres 19 for supplying secondary air to oxidize or burn the metallic vapors into fume. Passing out at one side of the shaft is a fume trunk 20 leading fume and gases to cooling devices, bag filters, etc., not shown. The air used in the upper row of tuyeres may .be heated at the expense. of the sensible heat of these fumes and gases by means of heat recuperating fines or the like and sent to the tuyeres through pipe 21.

In the use of the apparatus shown, a suitablecharge of ore, flux and fuel is deposited in the apparatus by removin plate 4. The. level of the charge is somew ere below the top of element 7. I recommend a depth of about 15 inches for this charge; but a greater or less depth may be employed. The charge is brought to incandescence by hotair from any suitable air heating device coming through trunk 10 and passing into the charge. Zinc and lead, etc., volatilize and pass out of the charge as invisible metallic vapors which are oxidized or burnt with intense evolution of heat, into visible fume by more hot air entering through tuyeres 19. The resultant fumes passforward through fume trunk 20 to a place of collection and disposition. In starting, the charge is usually'made up with coarse ore, flux, etc.,coarse enough to allow free passage of blast through it. When the charge is established fine ore from hoppers 15 may be fed through pipes 17 and 14 and forced into the mass by injector 11'. The fine ore so fed may thereafter if desirable constitute the chief source of supply for ore in the charge. Additional coarse ore may, of course. also be supplied. The non-volatile metals, copper and gold, with some silver, form amatte with the aid of the sulfur and iron always present in these complex ores and this matte is tapped out at 18. The ten'iperatures are maintained high enough to form a clean'fiuid slag.

As will be noted, in the present method I am efiecting a separation between relatively volatile and relatively non-volatile metals, the former being converted into vapor or gas which is then burnt into fume and collected, while the latter are converted into matte. other conditions in the charge the oxygen Because of the temperature and of the hot air blast and the carbon of the charge for the most part burn to CO, creating highly reducing conditions within the mass of the charge, while above the char e the CO and the volatilized metals, sulfids and sulfur burn with development of an intense heat which radiates down upon the relatively shallow bed of the charge, aiding materially in keeping its temperature at the high plane required to form and fuse clean hi h silica slags.

Vhat I claim is 1. The process of treating complex refractory ores containing relatively volatile and relativel non-volatile metals as well as sulfur which comprises e tablishing and maintaining a relatively low. .tl'g of ore, flux and fuel at a temperature sufiicient to form and fuse hi hly siliceous slags, supplyinghot blast thereto in the amount require to form liquid matte and vapors carrying the volatile metals; burning the vapors passing away from the char 'e by hot air introduced at a spaced point a ove the charge level and collecting the oxidized fume so produced.

2. The process of treating complex refractory ores containing relatively volatile and relatively non-volatile metals as well as sulfur which comprises establishing: and maintaining a relatively low charge of ore, flux and fuel at a temperature sufficient to form and fuse highly siliceous slags, supplying hot blast thereto in the amount required to form liquid matte and vapors assiug away from the charge of the v0 atile metals, fine ore being blown into said charge by and with said air; burning the vapors by hotair introduced at a spaced point. above the charge level and collecting the oxidized fume so produced.

3. In. matte smelting of complex ores.

carrying zinc or other relatively volatile metals, the process which comprises smelting such an ore in admixture with fuel and flux as a shallow bed at matte and slag making tern eratures by injected hot blasts, the blast being introduced in such amounts and in such condition as to produce liquid slag and mat and the effluent ases and vapors coming from such bed bein bhrnt or oxidized at a spaced point therea ve by secondary air to aid in maintaining-the temperature of such bed by radiant heat.

In testimony whereof, I havehereunto affixed my signature.

. WILLIAM GEORGE WARING. 

